Meteorites may have delivered phosphorus

Phosphorus is an essential atomic ingredient in DNA, RNA, and cell membranes. But, compared with other must-have elements such as carbon, hydrogen, oxygen, and nitrogen, phosphorus is the least abundant on Earth, says Matthew Pasek of the University of Arizona in Tucson. With so little phosphorus in the terrestrial environment, Pasek wondered how life could have emerged on Earth 4.5 billion years ago. The answer, he proposes, is meteorites.

Phosphorus occurs naturally on Earth in the form of the mineral apatite. However, previous experiments showed that dissolving apatite in water releases only small amounts of phosphorus, presumably not enough to have supported the origin of life.

In recent years, evidence has been accumulating for the theory that meteorites supplied Earth with large amounts of organic material, providing the necessary building blocks for making the first forms of DNA, prot

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